Molecular cloning and expression of a cDNA encoding the luciferase from the firefly, Pyrocoelia rufa

To clone a cDNA encoding the luciferase of the firefly, Pyrocoelia rufa, we have constructed a cDNA library and isolated the luciferase gene using PCR with gene specific primers. Sequence analysis of the cDNA encoding the luciferase of P. rufa revealed that the 1647 bp cDNA has an open reading frame of 548 amino acid residues. The deduced amino acid sequences of the luciferase gene of P. rufa showed 98.9% homology to that of P. miyako. Phylogenetic analysis further confirmed the deduced amino acid sequences of the P. rufa luciferase gene belonged to the same subfamily, Lampyrinae. Southern blot analysis suggested possible presence of the P. rufa luciferase gene as a single copy and Northern blot analysis confirmed light organ-specific expression pattern at the transcriptional level. The cDNA encoding the luciferase of P. rufa was expressed as a 69 kDa band in baculovirus-infected insect cells and the recombinant baculovirus-infected cell extracts emitted luminescence in the luciferase activity assay.